Played Around with Drupal, Upcoming Site Update, and more …
I hadn’t write any blog post since last Thursday. The reason is because I had been playing around with Drupal. Drupal is a Content Management System that is similar to WordPress, in my experience, because it can install additional plugins as modules, custom themes, and add pages. However, Drupal has few other features that need to be configured externally if using WordPress, such as the ability to optimize the performance of the site by enabling compression. Perhaps I used WordPress for long time and don’t know how to use Drupal yet, I have not discovered any usefulness of Drupal over WordPress yet. I will continue to learn more about Drupal and improve my Drupal site at diary.robbychen.com. As you can see through the URL, I originally planed to start another diary blog using a CMS app and change the daily post schedule for this blog to irregular post schedule just like my Tumblr-based blog. I decided first to try Drupal because I tried Joomla before and I can’t seem to use it. I think I will try other CMS if Drupal also won’t work for me.
I also plan to update my main site robbychen.com beginning tomorrow since the spring semester is over. I decided to make this site as a portfolio site that include all the programming works that I have done in the past instead of a tutorial site because this domain name is based on my name and it doesn’t suited for a tutorial website or a commercial website. The current layout on the site is based on a commercial website. I will try to create my own site layout and I have decided to apply the color theme of the site based on the new Ubuntu Radiance theme.
Click to enlarge
The ColdFusion to PHP project that I was promised back in January is not possible anymore because I couldn’t find the CA 278 files and can’t convert to PHP without these files. However, I’m organizing the CA 288 class files which is advanced ColdFusion programming. I will rewrote them with PHP as soon as the maintenance of these files is completed.
Delete part of the URL string using removeChars with ColdFusion
While I was doing the final project for my ColdFusion class today, I got one problem which the URL query keeps adding up when I was using CGI.QUERY_STRING. For example, the query string becomes “projectid=5&clear=yes” when I just added the “&clear=yes” to the end of the CGI.QUERY_STRING variable. After the page have been refreshed, the query would become “projectid=5&clear=yes&clear=yes”. This became a problem to me because not only the URL query was not right, but the result of the page was also not right.
After numerous trail of using cfif, I remembered that I could use a build-in ColdFusion function to remove the last part of URL query and store it to a variable to use it later. The name of the function is removeChars. It needs three parameters, a string, the position number of where to begin removing characters, and the position number of where to end the removing of characters. For example, I used the following statement to remove the “&clear=yes” characters at the end of the CGI.QUERY_STRING variable and stores it to a new variable called variables.QUERY_STRING:
<cfset variables.QUERY_STRING = removeChars("#CGI.QUERY_STRING#",12,11)>
Of course I would add a cfif statement to avoid continue removing the characters if there is no “clear=yes” exists in the string:
<cfif CGI.QUERY_STRING CONTAINS "Clear=yes">
<cfset variables.QUERY_STRING = removeChars("#CGI.QUERY_STRING#",12,11)>
<cfset variables.clear = "#CGI.QUERY_STRING#">
<cfelse>
<cfset variables.QUERY_STRING = "#CGI.QUERY_STRING#">
<cfset variables.clear = "#CGI.QUERY_STRING#&Clear=yes">
</cfif>
<a href="?#variables.QUERY_STRING#" title="Continue Shopping">Continue Shopping</a><br />
<a href="?#variables.clear#" title="Clear Cart">Clear Cart</a>
You can see result of the above code here along with my final project.
Create a DSN-less database connection using ColdFusion 8
For a long time, I had been searching around online to find a solution to switch to MySQL database for my ColdFusion school server from Microsoft Access database. Since I have no control over the ColdFusion Administration settings, I can’t change the DSN connection.
Recently I have been finishing my remaining undone projects. I use Railo open source CF server and MySQL under Ubuntu to do the assignments for the class. The SQL code I was writing is a bunch of aggregate functions:
SELECT Â b.BookId, Â Â Â b.BookTitle, Â s.SalePrice, Â Â Â Â Â Â COUNT(s.SalePrice) AS bcount, Â Â Â Â Â Â SUM(sd.TotalSale) AS ts, Â Â Â Â Â Â SUM(sd.Quantity) AS qt FROM tblBooks AS b, Â Â Â tblSales AS s, Â Â Â Â tblSalesDetail AS sd WHERE b.BookId=s.BookId AND s.SaleId=sd.SaleId AND s.SalePrice IS NOT NULL GROUP BY b.BookTitle ORDER BY #variables.ob# #URL.s#;
When I was testing these code on the localhost which is MySQL-powered, the page was rendered fine without any errors. However, once I uploaded to the school server which is powered by MS Access, the errors began to appear. Noticeably, I can’t use the name such as b.BookId, b.BookTitle, s.SalePrice without using aggregate functions. It struggled me a bit because the final is due tomorrow.
I then remembered my unsolved solution for connecting MySQL database dynamically through CF code because most of the DSN-less code online only works in CF 5. Once again I began to searching for the solution to release my struggle to the MS Access. Finally, I found a CF custom tag to do just that. It is called query, similar to cfquery. Since it’s a custom tag, the use of it is cf_query. This tag is primary used to connect to the MS SQL server by its author. Fortunately he has given a code snippet to dump out the available JDBC drivers on the server.
After I tested this code, I was surprised to see that my school server supports lots of databases that I don’t know about. I chose the MySQL one and copied its JDBC URL to the CF test page. I noticed that I was unable to connect to my own MySQL server on this web server since my hosting provider doesn’t allow remote connection to MySQL. Therefore I googled for “free mysql hosting” and found a website called FreeSQL.org that specifically for hosting free MySQL databases. I connect to this newly created database by using the cf_query code:
<cf_query jdbcURL="jdbc:mysql://www.freesql.org/ColdFusion" username="username" password="password" qName="qGetData">
Note that ColdFusion is the database name. Within the cf_query beginning and ending tag, I wrote the SQL statements to import the data since the phpMyAdmin link does not work on FreeSQL.org. After that, I replaced the above cf_query code with cfquery in the project that I struggled with.
You can download the above code here along with the custom tag and the original code from its author. The project page that I was struggled with can be found here.
Calculate the degrees from the given Data to draw PHP Graph
During the final exam for my PHP class today, I encountered a math problem that I learned long time ago. The problem is to draw a chart based on the data from the database in order to show the ratio between men and women on a pie chart. The number of men represented as blue and red represent as women. I thought that it was as simple as draw two arcs using imagefilledarc function. However, when I noticed that the data needs to be in degrees in order to use this function. I totally forget how to convert a number to a degree since I haven’t been practice math for two years. Thanks to Google, I learned how to do the conversion on Yahoo Answers. The formula that I came up with is the degree of each men and women equals the number of men or women divide by total number of men and women multiply by 360. Therefore I wrote the following code:
<?php
   $image = imagecreatetruecolor(300, 300);
   $blue = imagecolorallocate($image, 0, 0, 255);
   $red = imagecolorallocate($image, 255, 0, 0);
   $white = imagecolorallocate($image, 255, 255, 255);
   imagefill($image, 0, 0, $white);
$male = $_GET['m'];
   $female = $_GET['f'];
$total = $male + $female;
   $maleDegree = $male / $total * 360;
   $femaleDegree = $female / $total * 360;
imagefilledarc($image, 130, 130, 200, 200, $femaleDegree-270, $maleDegree-90, $blue, IMG_ARC_EDGED);
   imagefilledarc($image, 120, 130, 190, 190, $maleDegree-90, $femaleDegree-270, $red, IMG_ARC_EDGED);
imagepng($image);
   imagedestroy($image);
?>
The f and m variables are URL variables, which means I can pass the number of males and females inside the normal img tag:
<img src="3_image.php?m=<?php echo $numMale; ?>&f=<?php echo $numFemale; ?>" alt="Problem 3 - Graph" />
You can download the source code here to experiment with it. There is a MySQLÂ database file inside the downloaded archive, which it contains the needed MEMBERS table for this script.
Playing Around with PHP URL Extraction
I discovered today that there is a feature in PHP that can grab current URL through $_SERVER['REQUEST_URI'] and convert it into an array using explode function. I think this is extremely useful to me. Partly because I always wanted to have an URL that is similar to the URL for this blog. Another reason is that I don’t have to edit my sever configuration either directly or through PHP to achieve the same result. The method I use to create an URL that only contains the folder of the page, that is, the page is index.php, might be useful for small websites that have less than fifty web pages or possibly less. I didn’t test it on a large set of web pages because I just thought about using this type of URL format in the final project for my CA 282 class. It is a four-page project, therefore I cannot guarantee that it can work on a larger set of web pages. I personally think that it can become disorganized and confused once I have a little more web pages by using this method. Here is the code if you want to test it. Basically, it includes all the files inside the main index page based on the value at the last slash of URL, e.x. http://www.example.com/folder/item :
$currentURL = $_SERVER['REQUEST_URI'];
$URLpart = explode("/", $currentURL);
$endURL = $URLpart[sizeof($URLpart)-2];
switch ($endURL) {
case 'signup': // http://zebra0.com/Chen/final/account/signup/
include_once 'includes/signup.php';
break;
case 'login': // http://zebra0.com/Chen/final/account/login/
include_once 'includes/login.php';
break;
case 'account': // http://zebra0.com/Chen/final/account/
include_once 'includes/account.php';
break;
case 'signout': // http://zebra0.com/Chen/final/account/signout/
include_once 'includes/signout.php';
break;
default:
include_once 'includes/index.php';
}
And the index.php file inside each of the folder simply include the main index.php at the root of the project folder. Because of the nature of the included file, I used the dynamic path using PHP $_SERVER array to generate an absolute URL for the links and style sheets instead of the static ones.
Changing Website Topic
I have not updated my main website robbychen.com since I began to blog more often. Although I got this domain last year, I haven’t used it until this semester. At first, I didn’t have any ideas what to do with this website. I decided to temperately store my class assignments. My goal for this website became more clear after I began this blog. I plan to change robbychen.com topic relevant to the topic of this blog. It will contain video tutorials for GNU/Linux and web development. It will also include all of my web development projects, as well as their source code. But first I will redesign the website to fit the new topic. I plan to complete before this semester ends.
Google Maps API and ColdFusion
While I was experimenting with Google API for my CA 288 ColdFusion class final project, I discovered that the ColdFusion variables can be used within the script tag. So I tried it out. I put the cfoutput tag outside the script tag in order to use the ColdFusion variables inside the script tag. And then I added cfif statement inside script tag to set the default latitude and longitude values to New York if there is no URL variables. Here is the cfelse part of the code:
var co_lat=#URL.a#;
var co_long=#URL.o#;
initialLocation = new google.maps.LatLng(co_lat,co_long);
var marker = new google.maps.Marker({
position: initialLocation,
map: map
});
contentString = “<br />#URL.d#:” + “<br />” + “Latitude: ” + co_lat + “<br />” + “Longitude: ” + co_long;
map.setCenter(initialLocation);
infowindow.setContent(contentString);
infowindow.setPosition(initialLocation);
infowindow.open(map);
I also used ColdFusion variables to convert them into the JavaScript variables as you can see on the first two lines of code. I also added a marker to the map to show the accurate location for the data provided. This is best used for creating maps from a list of places. For usage example, go to http://160.253.0.40/Students/Students/0111/browserGeo.cfm?d=Addo%20Entrance&a=-33.44431&o=25.73872. To download the source code, visit http://code.google.com/p/ca288-final-spring-2010-mc/downloads/list
PHP Form Validation Tip
While doing the assignment for my CA 282 PHP class today, I came up with a trick to minimize the amount of code that I need to write for the validation rule of each form element. This trick especially best used for validating forms with lots of form fields. The following is the PHP code:
if (isset($_GET['submitted'])) {
$field=”username,password,pwconfirm,fname,lname,address,city,state,zip,email”;
$fieldName=”User Name,Password,Confirm Password,First Name,Last Name,Home Address,City,State,Zip,Email”;
$field = split(“,”,$field);
$fieldNm=split(“,”,$fieldName);
for ($i=0;$i<10;$i++) {
if (empty($_POST[$field[$i]])) {
$errorMsg .= $fieldNm[$i].” is required.<br />”;
$success .= “False”;
}
else {
$success .= “True”;
}
}
if (!strstr($success,”False”)) {
$errorMsg=”The form successfully submitted.”;
}
}
else {
$errorMsg = “”;
}
echo “<div id=”noVal”>”.$errorMsg.”</div>”;
As you can see from the code above, I use split function to convert the combined form field names and the actual name for each form field to arrays. I then used a for loop to loop between form fields to validate the form. This is a simple form. It only checks all the form fields that left blank. You can use continue command inside the for loop for certain form fields that don’t need to be validated. You can also use email validation and password=password_confirm validation inside the for loop. Also note that the noVal id at the end of above code is just used to display the error massages to red color and bold.
The ColdFusion website is now fully data-driven
I learned a way to write code for the menus by using database instead of using cfswich. Now the course website is completely database-driven. I used the CMS approach to redesign the links in each menu. Here is the entire code for the content page that corresponce to the menu items:
<cfquery name=”qGetURL” datasource=”DSN0111″>
SELECT *
FROM tblMenu
WHERE 0=0 AND
<cfif isDefined(“URL.projectid”)>
menuID = #URL.projectid#;
<cfelseif isDefined(“URL.pageid”)>
menuID = #URL.pageid#;
<cfelse>
menuID = 18;
</cfif>
</cfquery><cfoutput>
<cfset filePath = ExpandPath(“#qGetURL.linkLoc#”)>
<cfif fileExists(filePath)>
<cfinclude template=”../#qGetURL.linkLoc#”>
<cfelse>
<div id=”noVal”>Not Found</div>
<cfinclude template=”index.cfm”>
</cfif>
</cfoutput>
As you can see from the above code, the file location and the file names are stored in the database instead of the page content. This way, I can create web pages inside site directories and then include it to the website through database without change the above code.
I also plan to create a ColdFusion web application that can directly update the database without launch MS Access. Right now I’m using CFEclipse to write the ColdFusion code on my Fedora system and virtualized Windows XP through VirtualBox to modify and viewing the database. My goal for this web application is to allow me to modify or view the database with less or no MS Access usage.
For those who don’t know, my ColdFusion course is Microsoft Access based, not MySQL based. I successfully installed ColdFusion 9 on my Fedora system, but I failed to install MS Access driver onto the system. That’s why I plan to create this application in the next few weeks.
Learning PHP Object Oriented Programming
Today I have learned about using Object Oriented Programming (or OOP) in PHP. It is very easy once you understand the structure of the OOP and have lots of practice on this technique. I learned this while I was looking over my Google Reader before my PHP class. I’m taking beginning PHP course this semester. This means that the OOP topic is not included in this course. You need to know basic PHP structures like functions and loops in order to understand OOP. Fortunately, I already self-learned PHP language during the end of year in 2009 through Lynda,com. So I tried to use OOP in the PHP script. At first. I think that I will practice more of this technique because this is new to me. I followed the simple tutorial on this website. After finishing the tutorial, I went to attend the PHP class. To me surprise, it had a test today. I happened to need more practice over the OOP. I took the second part of the test which was the hands-on test entirely using OOP. Here is the Object-oriented based test page. The following is one of the classes I created:
class todayDate {
public $month;
public $mesg;
public function __construct($tdMon) {
date_default_timezone_set(“America/New_York”);
$tdDate = date($tdMon);
$this->month=$tdDate;
switch ($tdDate) {
case “June”:
case “July”:
case “August”:
$this->mesg=”Drive safely: school is in session”;
break;
default: $this->mesg=”Enjoy your vacation: Drive safely”;
}
}
public function getMonth() {
return $this->month;
}
public function displayMsg() {
return $this->mesg;
}
}
I just learned the basics of Object Oriented Programming so I can only write these basic classes. As I learn more about OOP, I will improve my code for better readability and performance.
For more information and to learn more about Object Oriented Programming in PHP, visit this article on devarticles.com.